SCP-049-2 each spawn with their own subclass, divided into 4 (soon to be 5) rarities:

Common, Uncommon, Rare, Epic, Legendary,

Common: about 50% chance on revive

Uncommon: 40% chance on revive

Rare: 10% chance on revive

Epic: (currently not implemented)

Legendary: 0.1% chance on revive